There are various methods available for protecting the safety of the automotive vehicles and their occupants. Most automobile makers focus on soft shell vehicle with crumple zone, surrounded by a hard core to provide a safety cell for the passengers. The crumple zone concept is to receive collision impact energy by deformation units which spread the energy out into the body structure. The present crumple zones are basically a space provided to receive the deformed and twisted structures in case of a high-speed collision, but without a special device, the magnitude of the damage and its maximum crumple distance are not ascertained before the crash. Therefore this method is not always reliable. Although this crumple zone method is presently in use, its capacity relies mainly on the strength of the body-shell and the body-shell relies mainly on its shape and ductility of its material, soft enough to deform and absorb the impact energy. As for the composite structures, especially the carbon based fiber composite this crumple zone concept is not possible. Most composites are not suitable because of its brittleness and exhibit non-progressive characteristics when fail.
In the aviation industry, airplanes are built with very high safety standards and governed by regulations from FAA and or local civil airworthiness authorities. In aviation, airplane safety standards are changing every day based on findings from past crashes and incidences. Meeting the new safety margin is the challenge the aircraft designers have to face.
For example, the 9 g barrier requirements for bulkhead, massive load of reinforcement are needed to restrain the 9 g bulkhead. In order to meet the requirements, almost every stringer in the fuselage and the floor beams within the vicinity has to be reinforced to share the additional load. With the huge concentrated load, the attachments are susceptible to fatigue and a smaller possibility that the stringers might rip off before the 9 g design load is met in the event of a crash.
For the case of passenger seat, the seat tracks are require to withstand from 9 g to 16 g, a 77.7% increase in its design load. So much so that the seat-track has to be made from stronger material such as titanium and the seat manufacturer has to beef up their seats to match.
The high-speed impact energy dissipation device is designed to meet the demand for higher safety margin, especially at the high load concentration points. For example, a 9 g requirement, the device may be configured to activate at the design load depending on the aircraft design requirement. With the invention, the 9 g attachments may have to bear only the predetermined g load: whereby the remaining energy may be absorbed by the device.
The device concept is to isolate the high-speed impact energy from the vehicle crashworthy structures to reduce the possible fatalities of their occupants in case of a high speed collision. The device is to isolate the high-speed impact energy by dissipating large impact energy into many small manageable fragments. This high-speed impact energy dissipation device is based on a simple design concept. It is also small in size, light weight, easily adaptable and cost effective.
The concept of the invention is based on stresses produce by shocks. In theory, it is stated that any elastic structure subjected to a shock will deflect until the product of the average resistance, developed by the deflection, and the distance through which it has been overcome, has reached a value equal to the energy of the shock. It follows that for a given shock, inversely proportional to the deflection. If the structure were perfectly rigid, the deflection would be zero, and the stress infinite. The effect of the shock is therefore, to a great extent dependent upon the elastic property of the structure subjected to the impact.
The energy of a body in motion if collided may be spent in each of the following conditions:    1. In deforming the body struck as a whole,    2. In deforming the moving body as a whole,    3. In partial deformation of both bodies on the surface of contact (most of this energy will be transformed into heat),    4. Part of the energy will be taken up by the structures, if these are not perfectly rigid and elastic.
The above conditions are applicable to a body in motion when it is involved in a collision. The nature of the impact may vary either in one or more than one of the above conditions.
The object of the present invention is to design a device to spend the impact energy into the forth condition by substituting the deformable body structures with the device.
The capacity of the device is based on Newton's Third Law of Motion, where the magnitude of the impact energy or the ‘work done’ is predetermined by the body-shell of the vehicle. Similarly, for the case of a helicopter, when dropped from a height, large potential impact energy may also be determined. With these conditions and their extreme impact forces, so far no single device is capable to absorb such an extreme magnitude without causing less fatality to the occupants.